激光直接制造工艺对Ni合金成形的影响

选用Ni60合金粉末材料进行了简单零件的激光直接成形试验,借助金相分析、扫描电子显微分析,研究了不同加工工艺对其成形的影响。结果表明:零件成形的宏观质量与单道熔覆层厚度关系密切,在激光功率1100W、激光扫描速度2～3mm/s、送粉量70～100mg/s条件下可获得外观光滑的零件;在送粉量一定的情况下,成形过程熔覆层的高度波动与零件形状有关,可以通过调节扫描速度来改善其高低不平的程度;克服制造缺陷的方法是注意基体的预热和成形零件的缓冷处理,激光功率和扫描速度需要在加工过程中适当调节。     

激光工艺参数对高硅铝熔覆层组织及性能影响研究

采用LWS-1000型Nd∶YAG激光器在1050铝合金表面激光熔覆制备高硅铝熔覆层。探索不同激光功率和扫描速度对熔覆层质量的影响,分析熔覆层的微观组织,测试熔覆层的硬度和耐磨性能。结果表明:在优化工艺参数下(激光功率170W,激光扫描速度200mm/min)制备出的高硅铝熔覆层与基体结合良好、组织致密、无气孔和裂纹,熔覆层中存在大量初晶硅,未发现明显共晶组织。熔覆层的横截面硬度值达到245HV,进行耐磨性测试后,相比基体耐磨性能明显提高。     

组合自固型无螺栓高铬铸铁球磨机衬板在我厂的应用

通过球磨机的生产运转情况，论证了组合自固型无螺栓高铬铸铁衬板应用的可靠性和稳定性及其在生产实践中的经济效益。     

邯钢CSP线卷形缺陷分析

介绍了邯郸钢铁股份有限公司CSP生产线上常见的错层、折边、塔形、塌卷等卷形缺陷的特征，分析了缺陷产生机理，并提出了相应的预防措施。     

梯度过渡复相陶瓷涂层的制备及其耐磨性能研究

采用幂函数分布形式设计梯度过渡涂层，以Ti-B4C—C团聚粉和Ni-A1自粘结复合粉的混合物为自蔓延反应火焰喷涂体系，在45号钢基体表面制备了Ti（Cx，Ny）TiB2和NimA1n梯度过渡的复相陶瓷涂层，研究了梯度过渡涂层的组织特点与耐磨性能。研究表明，当梯度指数为1，涂层按6层设计时，涂层为典型的多相非均质结构。Ti（Cx，Ny）-TiB2复相陶瓷与NimA1n金属间化合物实现了沿涂层厚度方向的梯度过渡连接。梯度过渡陶瓷涂层的耐磨性是普通45号钢耐磨性的14倍，涂层磨损失效过程受粘着磨损与磨粒磨损共同作用，失效过程中陶瓷相的剥落是涂层磨损的关键环节，涂层中的粘接相、氧化物相和孔隙对涂层磨损有重要影响。     

设备技术改造支撑企业的发展

本文着重介绍近几年来对热处理设备进行技术改造,改善了设备的各项综合性能指标,提高了产品质量、降低了成本,使企业走向良性循环发展.     

尾砂与戈壁集料胶结充填试验研究

在盘区下向进路回采过程中,我矿采用了全戈壁集料混凝土泵送胶结充填方法,其成本较高,且有继续增加的可能性。本文通过原因分析,初步论述了为了降低充填成本,利用选矿分级尾砂,保护环境,采用尾砂与戈壁集料胶结充填的可能性。     

Effect of ultrasonic stirring on temperature distribution and grain refinement in Al- 1.65%Si alloy melt

A series of experiments were conducted for Al-1.65%Si （mass fraction） alloy melt to study the formation of grain refining structure with ultrasonic stirring. The cooling curves of ingots with ultrasonic were measured and compared with those without ultrasonic. At the same time, the effect of the time of ultrasonic stirring on solidification structure of ingots was investigated. The influence of ultrasonic on the grain-refining efficiency of ingots was analyzed. In order to well understand the melts behavior under ultrasonic, by using ammonium chloride solution, the simulation experiment was carried out and the temperature distribution in ingot with or without ultrasonic was compared. The results indicate that the ultrasonic reduces the temperature inhomogeneity of melt, i.e. the ultrasonic helps to homogenize the melt temperature. The effect of stirring and heat generation in ingot start to occur with increasing the time of ultrasonic stirring.     

Preparation of oriented linear copper fiber sintered felt and its performance

Long metal fibers were manufactured in horizontal lathe with a multi-tooth tool. Based on the coarse antler surface structure of copper fibers, a new sintering technology was put forward to manufacture a kind of oriented linear copper fiber sintered felt. The sintering mechanism of oriented linear copper fiber sintered felt was studied. Compared with sintered copper-wire felt, the characteristics of sintered copper-fiber felts were analyzed in details. Owing to the coarse antler surface structure of copper fibers, oriented linear copper-fiber felt was sintered under the condition ofmicro/nano scale range, and copper fibers easily bonded together in the sintering process. Microchannels with micro-scale coarse antler surface structure were constructed. These characters give oriented linear copper fiber felt some new merits： high filtration accuracy, high flow capability, low resistance loss, good capability to resistance pressure, stable and uniform pore, high specific surface area. The properties of oriented linear copper fiber sintered felt were analyzed.     

气动连杆机构优化设计关键技术研究

在CAD系统中完成气动连杆机构几何实体概念设计和早期设计,在MATLAB中完成机构优化设计,并在VC下编制接口应用程序实现两者之间的数据传输,运行该程序能使基于MATLAB的气动连杆机构优化设计得到的优化结果直接更新早期几何模型.研究结果表明:该方法可以发挥UG强大的参数化建模功能,并能有效利用MATLAB出色的数值计算能力,为用户化机构优化设计提供了理论依据.